Protein Test is First to Predict Rate of Progression in Lou Gehrig’s Disease
A novel test that measures proteins from nerve damage that are deposited in blood and spinal fluid reveals the rate of progression of amyotrophic lateral sclerosis (ALS) in patients, according to researchers from Mayo Clinic’s campus in Florida, Emory University and the University of Florida.
Their study, which appears online in the Journal of Neurology, Neurosurgery & Psychiatry, suggests this test, if perfected, could help physicians and researchers identify those patients at most risk for rapid progression. These patients could then be offered new therapies now being developed or tested.
ALS - also known as Lou Gehrig’s disease - is a progressive neurodegenerative disease caused by deterioration of motor neurons (nerve cells) that control voluntary muscle movement. The rate of progression varies widely among patients, and survival from the date of diagnosis can be months to 10 years or more, says Kevin Boylan, M.D., medical director of the ALS Clinic at Mayo Clinic in Florida.
“In the care of our ALS patients there is a need for more reliable ways to determine how fast the disease is progressing,” says Dr. Boylan, who is the study’s lead investigator. “Many ALS researchers have been trying to develop a molecular biomarker test for nerve damage like this, and we are encouraged that this test shows such promise. Because blood samples are more readily collected than spinal fluid, we are especially interested in further evaluating this test in peripheral blood in comparison to spinal fluid.”
There are no curative or even significantly beneficial therapies in clinics now for ALS treatment, but many are in development, Dr. Boylan says. A test like this could help identify those patients who are at risk for faster progression of weakness. With experimental treatments that primarily slow progression of ALS, detecting a treatment response in patients with faster progression may be easier to detect, says Dr. Boylan. Now, patients with varying rates of progression participate together in clinical studies, which can make analysis of a drug’s benefit difficult, he says.
Lou Gehrig’s disease, also called amyotrophic lateral sclerosis (ALS), causes the nerve cells in certain regions of your brain and spinal cord to gradually die. Eventually, people who have Lou Gehrig’s disease (ALS) lose the ability to move their limbs and the muscles needed to move, eat, speak and breathe.
Doctors don’t know what causes Lou Gehrig’s disease, and the disease can’t be cured. Although doctors can’t reverse the progression of Lou Gehrig’s disease, advances in treatment mean that many who have the disease live longer than they did in the past. Each year about 5,000 Americans are newly diagnosed with ALS, and about 20,000 Americans have the disease.
Lou Gehrig’s disease first gained widespread public attention in the United States in 1939. Doctors at Mayo Clinic diagnosed baseball player Lou Gehrig’s condition.
“If there were a way to identify people who are likely to have relatively faster progression, it should be possible to conduct therapeutic trials with smaller numbers of patients in less time than is required presently,” Dr. Boylan says.
Researchers from Northwestern University are reporting a major breakthrough in understanding of the cause of amyotrophic lateral sclerosis (ALS), the fatal disease also known as Lou Gehrig’s disease.
They say their discovery proves that different forms of ALS actually have a common cause and that this could lead to better strategies to treat the disease.
Their study was reported online in the journal Nature.
In ALS, nerve cells in the brain and spinal cord that control movement stop functioning. The condition leads to paralysis, and patients eventually cannot breathe or swallow on their own.
The disease afflicts about 350,000 people a year worldwide, and about half of patients die within three years of diagnosis.
A longer-range goal is to develop tests of this kind to gauge how well a patient is responding to experimental therapies, he adds.
The test measures neurofilament heavy form in blood and spinal fluid. These are proteins that provide structure to motor neurons, and when these nerves are damaged by the disease, the proteins break down and float free in blood serum and in the spinal fluid. Earlier research in this area was conducted by Gerry Shaw, Ph.D., a neuroscientist at the University of Florida, who is the study’s senior investigator and the developer of the neurofilament assay used in the study.
The researchers measured neurofilament heavy form in blood and spinal fluid samples from patients at Mayo Clinic and at Emory University, and correlated levels of the protein with rate of progression. “We demonstrated a solid association between higher levels of this protein and a faster progression of muscle weakness,” Dr. Boylan says. There was also evidence suggesting that ALS patients with higher protein levels may have shorter survival, he adds.
Q. Why is ALS sometimes called Lou Gehrig’s Disease?
A: Many years ago, Lou Gehrig was known as professional baseball’s
“Ironman.” With strength, agility, and excellent health, Gehrig had everything
it took to become a baseball legend. At the peak of his career, he was diagnosed as having Amyotrophic Lateral Sclerosis (ALS) and died 2 years later, at age 39.
Q. What are the early symptoms of ALS?
A. ALS usually becomes apparent either in the legs, arms, throat or upper chest area. Some people begin to trip and fall, some lose the use of their hands and arms, some find it hard to swallow and some slur their speech.
Since the disease frequently takes its toll before being positively diagnosed, many patients are debilitated before learning they have ALS. The disease wreaks a devastating effect on patients as well as their families.
As they struggle to cope with the prospect of advancing disability and death, ALS patients may find their financial, physical and emotional resources exhausted. It is a costly disease in its later stages - demanding both expensive nursing care and equipment.
Q. How do you “catch” ALS?
A. ALS cannot be “caught” - it is not contagious. In 90% of cases, ALS strikes people with no family history of the disease. Only 10% of cases are classified as familial or inherited. It may occur at any age, with the risk increasing as people grow older. However, many people are struck down in the prime of life.
The work was funded by the ALS Association, the Packard Center for ALS Research, MCF ALS Center Donor Funds and Mayo Foundation.
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